In order to keep the harmonic content and waveform distortion rate in the power supply system within the specified values, it is necessary to know the actual harmonic content in the grid, which can be calculated by theoretical analysis and actual measurement.

Spectrum analyzer is a more suitable instrument for measuring EMI. Spectrum analyzer is the instrument displaying voltage amplitude change with the frequency and its waveform called spectrum.

Active power is the power to make the machine working, in another word, the electric power to transfer electric energy to other mode energy, such as mechanical energy, optical energy, heat energy, etc.

Multimeters are one of the necessary instruments for hardware engineers, they can measure voltage, current, resistance, capacitance, diode, etc.

Nowadays many brands of rf signal generator are existing in the market, it will make double results with half work by selecting a suitable product in your test and measuring work.